Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: HLDLILXDRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
309-658 A Hillsdale IL 1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 634      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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